Multiflow cooling system for internal combustion engines



F. w. HILD 2,075,521

MULTIFLOW COOLING SYSTEM FOR INTERNAL COMBUSTION ENGINES March 30, 1937.

Filed Nov. 10, 1930 Patented Mar. 30, 1937 MULTIFLOW COOLING SYSTEM FOR INTER NAL COIVIBUSTION ENGINES Frederic W. Hild, Los Angeles, Calif.

Application November 10, 1930, Serial No. 494,567

35 Claims.

My invention relates to cooling systems for internal combustion engines and appertains more particularly to those for automotive vehicles.

It is an object of my invention to provide a multifiow cooling system which shall more eiliciently utilize the water cooling radiator and which shall comprehensively regulate the engine temperatures for all loads.

In my co-pending application, Serial Number 490,480 filed October 22, 1930 I have disclosed a novel cooling system for internal combustion engines. It is an object of my present invention to further improve my said cooling system by providing it with simple and effective means for l5 rapidly warming a cold engine.

Other objects and advantages of my invention will be apparent from the following description and the accompanying drawing:

Figure 1 is a vertical elevation in part section showing the apparatus embodying my invention.

Figure 2 is a horizontal section taken on the line 2--2 of Figure 1.

Figure 3 is a sectional view taken on line 33 of Figure 1 and illustrates the manually operated valve of the ejector flow inducer.

Figure 4 is a sectional view of the valve controlled ejector fiow inducer taken on line 4 4 of Figure 3 and also shows the upper tank of the radiator.

Figure 5 is a vertical sectional view of a modifled automatic valve of the ejector flow inducer.

Referring to the drawing, the radiator 6 is air cooled by fan I which is driven by the engine 8'in the usual manner. The radiator has an up- 35 per 'tank 9 and a lower tank In which are connected together by cooling core II. The core consists of the tubes l2 and the fins l3, the tubes providing numerous water channels leading from the upper tank to the lower tank. Air drawn through the core ll cools the water in the tubes.

The lower tank has two openings or outlets l4 and I5 respectively. A pump [6 connects with the lower tank at outlet 14 and is in turn connected by a pipe I! to water channels l8 which jacket the' engine cylinders in the customary manner. The said water channels communicate with manifold l9 which connects with the ejector flow inducer 20 which in turn connects with upper tank 9 in theopening 2|. By means of the pump. water under pressure may be circulated from the lower tank l0 through the water channels l8, manifold 19, ejector flow inducer 20, and opening 2| into upper tank 9 and descending through cooling core H to the lower tank ID. A 55 From the opening I5 of lower tank [0, a tube 22 for conducting water is connected with one end of a heat exchange device 24, such as a coil of tubing disposed in the oil reservoir in the bottom of crank case 23 of engine 8. The coil 24 surrounds the customary oil pump 25; both the coil and the pump are submerged in the lubricating oil in the reservoir, the oil pump forcing the oil to the various parts of the engine in the usual manner. The other end of coil 24 connects with the riser tube 26 which connects with flow inducer 20, the fiow inducer-as pointed out conmeeting with upper tank 9.

The fiow inducer 20 has water passage 21 which connects with manifold l9, and it also has water passage 28 which connects with riser tube 26. The passage 21 extends into and is surrounded by passage 28 and both passages lead into common orifice 29. Passage 21 may be aptly termed a nozzle.

A valve disposed in the orifice 29 controls the fiow of water from the inducer 20 to upper tank 9. The valve 30 which swings upward to efiect closure has valve stem 3| which is journaled in the walls of orifice 29 and projects through one wall of the orifice into-the adjacent compartment 32 of the flow inducer 20. The projecting end of the valve stem is bent upward to form a lever with a suitable opening at the end of the lever for receiving a pair of links 33. A spring 34 is secured to an end wall of compartment 32 and to one end of each of links 33; the,

spring being always in tension operates to pull the valve 30 into open position. The other end of each of links 33 is pivotally secured to the closed end of a bellows 35 which also is contained within the compartment 32. The other open end of the bellows 35 is secured fluid tight into the compartment by guide nut 36 and jam nut 31 both of which are threaded into the other end of compartment 32. A cover plate 38 is secured to the open side of compartment 32, this cover plate and the bellows 35 preventing leakage of water which might seep through the journal bearing for the valve stem.

A spring link 39 is secured to the valve operating mechanism. The spring link comprises two terminal members with a spring disposed between them, such that pull or tension on the terminal members will compress the spring and will lengthen the spring link assembly, until the spring is compressed to its limit.

One terminal of spring link 39 is slidably supported by guide nut 36 and is firmly secured to the closed end of bellows 35. The other terminal of. spring link 39 is secured to an end of intermediate lever 40 and also to an end of choke rod 4|. The choke rod extends to and terminates in a choke handle (not shown).

The intermediate lever 40 is fulcrumed on car- 5 buretor 42 the other end of the lever having a slot 43 in which the end of choke lever 44 is slidably secured. The choke lever 44 is part of the gas admission mechanism of the engine, its function being to control the admission of raw unvaporized gasoline from the carburetor to the engine. A spring 45 always in tension, operates i to pull and hold choke lever in opened position.

It is well understood that in order to start a cold engine it is usually necessary to operate the 5 choke lever to cut off the air supply to the carburetor and thereby admit unvaporized gasoline to the cylinders until the engine and carburetor are warmed sufliciently to operate with gas vapor. It is important that the engine be warmed quickly, and this is accomplished by the herein described apparatus in the following manner:

A pulling force upon the choke rod 4| is transmitted by spring link 39 to the flow inducer valve mechanism consisting of bellows 35, link 33, valve stem 3| and valve which are thereby moved against the resistance of spring 34 into the position of valve closure where further movement of the valve mechanism is stopped. Meanwhile the intermediate lever pivoting on its fulcrum will 30 have been moved to the limiting position of slot 43 so that choke lever 44 is against the end of the slot. In response to continued pulling movement of the choke rod 4| and the permissive lengthen ing of spring link 39, the intermediate lever 40 will move choke lever 44 into position for feeding unvaporized gasoline to the engine cylinders. By this time the engine and the water pump it are being motivated by the starting motor or other suitable starting means and the engine begins to 40 run on the gasoline fuel whereupon the water cylinder jacket i8 becomes heated.

The valve 30 having closed the orifice 29 of the flow inducer 20, the water which is being forced through the water jackets l9 and manifold i9 by the pump l6, cannot flow into upper tank 9 of the radiator, but is diverted in the flow inducer and forced through riser tube 25, coil 24 and tube 22 into the lower tank Hi to be again drawn into pump l6 and circulated as just explained. The

water entering the coil, which functions as a heat exchanger, is about as hot as the water in the manifold l9; and therefore the coil 24 becomes heated and transmits heat to the lubricating oil which in turn warms the engine parts reached by The circulating water as it leaves tube 22 and enters the lower tank ID will have lost some of its heat to the oil. Some heat transfer occurs from the warm water in lower tank It to the cold water 0 in cooling core mostly by convection, but the loss of heat is relatively small in view of the fact that the heated circulating water does not pass through the cooling core and is therefore not subjected to forced cooling by radiation.

5 Manifestly the engine warms very rapidly the fuel vaporizes more freely and smoothengine running quickly occurs. Thereupon the pull on the choke rod 4| and sprink link 39 which is manually exerted should cease, and due to the action of 7 springs 34, 45 and spring link 39,the valve 30 in the flow inducer is opened and the choke lever 44 operates to cut off the raw gasoline which is replaced by vaporized gas from the carburetor.

With the valve 30 of flow inducer 20 in open 7 position the water circulating through the water Jackets i8 and manifold it by the pressure of the pump l9, now flows through orifice 29 of the flow inducer into upper tank 9, then down through cooling core ii to lower tank III and again into pump IS, the circulation being continuous. At the same time the ejector flow inducer 20 due to the action 01' water passing through it under pressure and the considerable velocity imparted by the pump l6, induces the water in riser tube 28, coil 24 and tube 22 to flow into and through orifice 29. into upper tank 9 and down through cooling core Ii into lower tank i0 and again into tube 22 and repeating the cycle thereby establishing complete, continuous induced circulation of the cooling liquid. Passage 29 has a constricted throat form? ing a venturi adjacent the discharge opening of nozzle 21. The velocity of the liquid passing through the throat is thereby increased and materially increases the ejector action. The water thus circulated through coil 24 is now cooling water, as it is drawn from the bottom of tank It after passing through the radiator pipes l2.

Having described herein a simple manually controlled means for circulating the heated water from the cylinder water Jackets back again through the engine in close thermal association with the lubricating oil in the engine and conserving the heat by not subjecting the circulating water to forced cooling in the radiator, thereby rapidly and effectively warming the engine,I provide also a simple, automatic means for accomplishing the same operation, the same result and which possesses other important advantages and benefits as will be apparent.

Referring to Figure 5, this shows the flow inducer valve 30 operated by a thermostat immersed in the liquid entering the flow inducer 20. In this embodiment of my invention, the manually operated means are dispensed with, both the spring link 39 and the intermediate lever 40 being omitted and the choke rod 4| being connected directly to the choke lever 44 in the usual manner.

An opening 46 is provided in the wall separating the water passage 28 and compartment 32 so that liquid may freely enter the compartment. The riser tube 26 leads into the flow inducer at this opening so that a thermostat 41 in the compartment 32 is always immersed in the liquid passing through riser tube 26. The thermostat 41 is secured fluid tight into compartment 32 by the end cap 48. A guide post 49 projecting upward from the bottom of the compartment slidably supports the push rod 50 which extends into the re-entrant part of the bellows 41. A push cap 5| threaded on the end of push rod 50 bears against the thermostat. A compression spring 52 surrounds the push rod 50 and is interposed between the guide post 49 and the cap 5|. The spring 52 exerts resilient force to contract the thermostat, that is, the spring opposes the expansive power of the thermostat when the latter becomes heated. The other end of the push rod 50 is pivotally secured to an intermediate point of a pair of lever links 53 which are fulcrumed at the lower end on a suitable fulcrum 54 projecting forward from the bottom of compartment 32. A connecting link 55 is pivotally fastened near the other end of lever links 53 connecting the latter with the lever end of valve stem 3|. To the free. end of lever links 53 is secured one end of an adjusting spring 56, the other end of this spring having swivel connection with adjusting screw 51. This adjusting screw is threaded into a neck 58 which forms the top of compartment 32, the screwbeing locked into position by jam nut 59, a packing 60 between the jam nut and the adjusting screw 51 prevents leakage from the neck.

It is apparent that adjusting spring 55 which is always in tension and compression spring 52 both act to pull the valve 30 so that it will swing downward into closed position. Opposing the combined force of the two springs is the power of the thermostat H which expanding as it becomes heated by the water in which it is irn mersed, operates to open the valve 30.

The internal combustion engine being a heat engine, its theoretical efliciency is best at high temperature; but certain essential factors of engine operation determine the practical tempera- .ture limit. If the combustion chamber is excessively hot, pre-lgnition may occur. The greater expansion of the fuel mixture entering an over heated cylinder before compression, results in decrease of power. If the cylinder walls become very hot, the lubricating oil becomes too thin and may fail with consequent friction difliculties resulting in excessive wear of the engine parts and even seizing. It is generally recognized that lubrication determines the practical upper temperature limit and when this is not exceeded, all the essential engine factors will have safe margin as affected by temperature.

In the cooling system herein described, it will be observed that when valve 30 is closed, the thermostat 4! is in the path of the water flowing from the cylinder water jackets. The two water channels in the engine (water jackets l8 and manifold i9 being one, and the coil 25 being the other) are in series with each other, the water flowing in a single circulating stream through this series path toward and through the lower tank it and into pump it. The circulating stream does not pass through upper tank 9 nor cooling core ii and therefore is not subject to forced cooling.

When the water from the cylinder water jackets becomes sufiiciently heated, the thermostat l? expands, overcoming the resistance of springs 52 and 5! and gradually opens valve 30 in the flow inducer. When the valve opens part way the single stream is divided and becomes two streams at the flow inducer, one continuing to flow through the coil 24 to the lower tank and not subjected to forced cooling; the other stream enters the upper tank 9, flows down through the cooling core ll where it is forced cooled and then enters lower tank Ill. The warm stream from the coil 25 and the forced cooled stream from the cooling core meet and mix in the lower tank. All of the water of both streams passes through pump IS, the cylinder jackets l8 and the manifold l9.

When the engine load increases demanding more fuel and therefore generating more heat, the thermostat opens the flow inducer valve more widely, resulting in more of the water from the engine cylinder jackets flowing into the upper tank of the radiator and less through the coil 24,

until a load condition is reached when the flow through the coil 21 ceases and all of the water flows into the upper tank. All of the circulating jacket l8. v

It is manifest that the ejector action in the flow inducer 2B depends upon sufflcient opening of the valve 30 and upon the velocity and pressure imparted by the pump IE to the water cirwater still flows through pump 96 and cylinder culating through the cylinder jackets II and manifold l9. The velocity and pressure of the water from the pump vary with the engine speed.

So that, the thermostat responding to the greater heat of the larger engine load, effects ample opening of valve 30; the suflicient ejector action in the flow inducer causing the water to flow from the lower tank through the coil 24 through the flow inducer and into the upper tank, then down the cooling core where it is cooled before it enters the lower tank. Thus the two streams circulating through the two cooling channels in the engine are no longer in series but are now in parallel relation; water flow in one of the channels has been reversed in direction; and all of the circulating water of both streams is new subject to forced cooling by the radiator cooling core. Because of the higher pump speed, more water now circulates through the pump and the cylinder jackets than before, but this constitutes only a portion of the water now circulating through the engine, the stream through the oil cooler being separate from and additional to that through the pump and the cylinder jackets. Also note that the water in which the thermostat is immersed now comes from the oil cooler and directly reflects the temperature of that factor which determines the upper temperature limit for safe engine operation, namely the lubricating oil.

It is manifest thatthe multiflow cooling system herein disclosed does not depend upon any thermo-siphon flow of the liquid in the cooling channels of the engine. Therefore any suitable supply of cooling liquid may be substituted for the radiator, which is but one example of a source of cooling liquid. Such a supply may be a river, or a pond; the valve controlled ejector enabling the pressure means to fill the engine cooling channels and "prime" them for the ejector. Moreover, the pressure means may be a city water line.

It is understood that the cooling system herein disclosed is such that the engine may have more than two water channels in one or more of which the liquid flows by induction. Also, that a single valve controlled flow inducer can be used to control the direction of water flow in a plurality of water channels and to cause flow in them either by induction or by pressure. It is obvious to those skilled in the art, that various other modifications may be made in the details of. construction, the general arrangement, the association of the several cooperating parts and the application of my invention without departing from the spirit thereof or the principles herein set forth.

I claim asmy invention:

1. In combination: a radiator, an engine having two separate cooling channels each in water circulating connectionwith said radiator, pressure means for imparting circulation to the water in said channels, and means for varying the diiiection of the circulation in one of said channe s.

2. In combination: a radiator for cooling a liquid, an internal combustion engine having means for causing circulation of said liquid through two separate channels in the engine, and means responsive to the rate of fuel consumption of the engine for automatically connecting said channels in series relation or in parallel relation.

3. In combination: a radiator, an engine having two separate cooling channels one of which is the cylinder jacket of the engine, the other channel being disposed in thermal association culating liquid from the radiator through a cooling channel in the engine, a vacuum means supplemental to the pressure means for circulating liquid from the radiator through another cooling channel, and valved means connecting both channels to the upper part of the radiator.

5. In combination: a radiator, an internal combustion engine, a pump for circulating liquid from the radiator through a cooling channel of the engine, and flow inducing means for creating a pressure difference and disposed in the path of said circulating stream for circulating liquid from the radiator through another cooling channel of the engine.

6. In combination, an internal combustion engine having a cooling jacket, a radiator incirculatory relationship with the jacket, a pump for forcing liquid from the radiator through the jacket, a heat transfer system having flow connections at its ends to two points in the circulatory system, and means for passing said liquid optionally in either direction through said heat transfer system.

7. In combination, an internal combustion engine having a cooling jacket, a radiator in circulatory relationship with the jacket, a pump for forcing liquid from the radiator through the Jacket, a heat transfer system having flow connections at its ends to two points in the circulatory system, and means for passing said liquid optionally in either direction through said heat transfer system, including a valve in one of said flow connections.

8. In combination, an internal combustion engine having a cooling jacket, a radiator in circulatory relationship with the jacket, a pump for forcing liquid from the radiator through the jacket, a heat transfer system having flow connections at its ends to two flow points in the circulatory system, one of said connections being between the jacket and the radiator and associated with the outlet of the jacket, said connection surrounding the outlet and connected to the radiator, and means for passing said liquid optionally in either direction through the heat transfer system.

9. In combination, an internal combustion engine having a cooling jacket, a radiator in circulatory relationship with the jacket, a pump for forcing liquid from the radiator through the Jacket, a heat transfer system having flow connections at its ends to two flow points in the circulatory system, one of said connections being between the jacket and the radiator and associated with the outlet of the jacket, said connection surrounding the outlet and connected to the radiator, and means for passing said liquid optionally in either direction through the heat transfer system, including a valve in said connection interposed between the radiator and the outlet from the jacket.

10. In combination: an internal combustion engine having a. cooling jacket, a radiator in circulatory relationship with the jacket, a pump for forcing liquid from the radiator through the jacket, a, heat transfer system having flow connections at its ends to two points in the circulatory system, one of said connections being between the jacket and the radiator and associated with the outlet of the jacket, said connection surrounding the outlet and connected to the radiator, and means for controlling the direction of heat transfer in the heat transfer system, including a valve in the said one connection.

11. The combination as defined in claim 10 with the addition of means responsive to the temperature of said liquid for operating said valve.

12. In combination: a radiator for cooling 9. liquid, an engine having two separate cooling channels for receiving said liquid, a pump forimparting forced circulation of said liquid through one said channels, and means supplemental to said pump for creating a pressure difference by the .aid of said forced circulation to induce flow of the liquid in the other channel.-

13. In a cooling system, the combination of: a

radiator, an engine having a plurality of separate cooling channels in water circulating connection with the lower part of the radiator, and means comprising a nozzle and a valve for connecting said channels to the upper part of the radiator.

14. A combination such as defined in claim 13 in which said valve is operatively connected to a thermostat disposed in the path of said circulating water.

' 15. A combination such as defined in claim 13 in which said valve is operatively connected to the gas admission mechanism of the engine.

16. In combination: a radiator, an engine having two separate cooling channels, a pump for circulating liquid from the radiator through one of said channels, flow inducing means supplemental to the pump and disposed in the path of said circulating stream for circulating liquid from the radiator through the'other of said channels, and means comprising a valve for controlling the circulation of said liquid.

17. In combination: a radiator for cooling a liquid and having two outlets from its lower tank, an engine containing a cooling channel for receiving said liquid, a pump connecting one of said outlets to said channel for circulating said liquid therethrough, a second cooling channel for the engine connected to the second of said outlets and bypassing the first channel, and means including a flow inducer and a valve for connecting both channels to the upper part of the radiator.

18. A combination such as defined in claim 1'7 in which said flow inducer means is an ejector having three passagesfor said liquid two of said passages being concentrically disposed both leading into the third passage which forms a common orifice for the other two and said third passage leading into the upper tank of the radiator, the said pump connected channel of the engine leading into the inner of the two concentric passages,

and the said second channel leading into the outer of the concentric passages; said valve in said means being disposed in the third passage.

19. A combination such as defined in claim 17 in which the said second channel is disposed in the oil reservoir of the engine.

20. In combination: a radiator for cooling a liquid, an engine having two separate cooling channels each of which has separate connection with the lower part of the radiator, positive pressure means for circulating said liquid through one of said channels, flow inducing means for circulating said liquid through the other chan ao'iaeai nel, and a valved conduit for connecting both channels to the upper part of the radiator.

21. A combination such as defined in claim 20 in which said valve is operatively connected to e the gas admission mechanism oi the engine.

22. In combination: a radiator, an engine having a cylinder jacket, an oil cooler for the engine,

a pump for circulating cooled water from the for circulating cooled liquid from the radiatorv through the other channel, and valved means for connecting both channels to the upper part of the radiator.

25 24. In combination: a radiator, an engine hav-' ing a plurality of separate cooling channels in water circulating connection with the lower part of the radiator, and a valve controlled flow inducer consisting of a housing containing a nozzle 30 and a valve and having a plurality of inlets for receiving the water flow from said channels and having a common outlet for connecting the flow inducer to the upper part of the radiator, said nozzle being disposed in axial alignment with 35 one of said inlets and said commonoutlet, said valve being disposed in the common outlet.

25. In combination, a radiator for cooling a liquid, an engine having two separate channels for receiving said liquid, 2. pump for imparting 4 torced circulation to said liquid through one of said channels, means for utilizing said forced circulation to create a pressure difference and thereby to induce flow of the liquid in the second of said channels, and valve means in the first of 45 said channels for regulating the circulation of said liquid in said second channel.

26. In combination: a radiator, an engine having two separate cooling channels, means for connecting each of said channels separately to 50 the lower part of the radiator, and means comprising an ejector for connecting both channels to the upper part of the radiator.

27. In a cooling system for an engine containing a cooling channel, the combination of: a

I 55 radiator, pressure means for circulating cooled liquid from the radiator through said channel, a second cooling channel connected to the radiator for receiving cooled liquid therefrom and bypassing the flrst channel, and means comprising 60 an ejector for conducting the liquid from both channels into the upper part or the radiator.

28. In combination: an internal combustion engine, a radiator for cooling liquid received from the engine, a pump for forcing cooled liquid from the radiator through the cylinder jacket of the engine, an oil cooler iorthe engine, a conduit for conducting cooled liquid from the radiator to the oil cooler, and an ejector fiow inducer for con-' ducting said liquid from the cylinder jacket and the oil cooler into the hot liquid receptacle of the radiator. r

29. In combination: a radiator for cooling a liquid, an internal combustion engine having a cooling channel and a heat exchanging channel, pressure means for forcing said liquid through one of said channels, and means including a nozzle and a constricted passageway in the path of said liquid for inducing flow of said liquid through the other channel.

30. In combination: an internal combustion engine having two cooling'channels adapted to receive a cooling liquid, one of said channels being a cylinder jacket, a pump connected to one of said channels for imparting forced pressure to saidliquid, and, means comprising an ejector for connecting said channels with each other and vfor receiving said liquid therefrom, said ejector having a. nozzle through which the liquid from the cylinder jacket enters the ejector.

31. The combination as defined in claim 30 in which said other channel is in thermal association with the lubricant of the engine.

32. In combination: an internal combustion engine having two separate cooling channels adapted to receive a cooling. liquid, and means connecting an end of one of said channels with an end of the other channel, said means comprising a valve for connecting said channels either in series relation or in parallel relation.

33. In combination: an internal combustion engine having two separate cooling channels adapted to receive a cooling liquid, one of said channels being the cylinder jacket of the engine, and means connecting an end of one of said channels with an end of the other channel, said means comprising a'valve for connecting said channels either in series relation or in parallel 

